1. Technical Field
The present invention relates to a liquid container and a liquid container set.
2. Related Art
To form a coating having metallic gloss on a printed article, some techniques have been used, such as foil stamping using a printing ink containing metal powder of, for example, brass or aluminum particles as a pigment, and thermal transfer using a metal foil.
Ink jet recording techniques have recently been used for printing in many cases. Metallic printing is one example of such cases, and inks that can form metal-glossy images are being developed. For example, JP-A-2008-174712 discloses an aluminum pigment dispersion containing an organic solvent such as alkylene glycol, and a non-aqueous ink composition containing the aluminum pigment dispersion.
On the other hand, in practice, aqueous ink compositions containing an aqueous medium are more highly desired than non-aqueous ink compositions containing an organic solvent from the viewpoint of global environment and human safety. However, if a metal pigment is dispersed in water, the surfaces of the particles of the pigment are sometimes tarnished due to deterioration or consumption cause by reaction with water.
To solve this issue, for example, JP-A-2011-132483 discloses a water-resistant aluminum pigment dispersion prepared by dispersing a water-resistant aluminum pigment whose surfaces are covered with a coating of silica or the like in an aqueous solution of a surfactant.
However, even though the surfaces of the pigment particles are covered with a coating, the reaction of the pigment with water cannot sufficiently be prevented and may cause hydrogen gas to be generated. In this instance, if an ink composition prepared by dispersing the pigment in an aqueous medium is stored in an air-tight container (for example, in an ink cartridge), the container may be seriously deformed or broken.